New Cat® C Series Knuckleboom Loaders Boast Fuel-Efficient Power Systems and More Lift

For Release in North America: April 2013

The new Cat® C Series knuckleboom loaders from Caterpillar Forest Products feature fuel-efficient power systems, upgraded hydraulics and significantly more lift at full reach than previous models. The line includes the Cat 579C loader, best for big wood, clear cutting and severe delimbing applications, and the Cat 559C loader, ideal for working in pine, pulpwood and thinning.

"Like previous models, the new C Series models are fast and smooth with superior multifunction capability. In addition to that, the C Series is more efficient and productive," said Blake Vaughn, Caterpillar Forest Products product performance engineer. "For example, in controlled lab tests the 559C was 22% more productive than the 559B burning the same amount of fuel."

The larger loader also now has a right-side operator's cab with a walk-up platform and enlarged doorway for safe access to the cab.

The C Series is powered by the 129.5 kW (174 hp) Cat C6.6 ACERT™ engine. In designing the engine to meet U.S. Tier 4 Interim emissions regulations, new technology was incorporated to ensure that changes would not reduce the life of the system, increase operating costs or reduce productive uptime. The automatic engine idle down feature and the variable speed engine fan that cools only as required, further reduce fuel consumption.

The 579C loader lifts 35% more at full reach, and the 559C lifts 25% more at full reach, compared to the previous models. "The boost in lift capacity is right where the operator can use it most — at full reach," Vaughn said. "The lift capacity in the previous models was already strong throughout the rest of the range of motion, so with the increase in lift at full reach, it gives operators that much more capability."

Three operating modes give loggers the flexibility to match hydraulic power to the job requirements, from thinning small pine to clear cutting big hardwoods. For normal loading operations, the Economy Mode provides fast cycle times and the most fuel economy. The Run Mode allows more hydraulic power for more demanding jobs and the Power Mode provides the most muscle for heavy duty delimbing, slashing and loading applications.

The C Series has an excavator-style Negicon piston pump hydraulic system, a robust, reliable system with a simple valve design and big spools to allow fluid to pass through easily. The increase in hydraulic line size also accelerates grapple opening and closing. "This hydraulic system is field proven. It's been a reliable platform for Caterpillar in other knuckleboom loader models, other forestry machines and excavators," Vaughn said. "This means more uptime, longer life and better performance."

A large side-by-side radiator, hydraulic and charge air cooling package efficiently expels heat. The individual cores are mounted separately on rubber isolators. This increases durability and also makes the cooling package easier to service. "When the cores are bolted tightly together, you will get some fatigue because they are cooling or warming at different rates," Vaughn explained. "This design eliminates that so the cooling package lasts longer."

Other improvements to increase the loaders' reliability include: solid state controls, Cat ToughGuard™ hoses and O-ring face seals, and beefed up boom tube clamps. "Loggers can just go out every day, turn the key and run the machine," Vaughn said.

A number of design changes improve serviceability. The filters for fuel, hydraulic oil, engine oil, pilot and case drain are all accessed and serviced standing safely on the ground. The hydraulic return filter is mounted on the outside of the hydraulic reservoir, a design widely used in excavators. "The capsule has a separate chamber that essentially locks in all the contamination that surrounds the filter. This eliminates contamination backflow during filter changes and completely removes any debris from the system," Vaughn explained.

Eco-valves, rather than plugs, are used throughout the machine so fluids can be drained without spilling. "Instead of just letting fluids fall into a pan and splashing on the machine or the ground, operators can connect a hose and run fluids into a container. It's a lot more convenient and cleaner because you don't have to clean up spilt fluids once you get done changing the oil," Vaughn said.

Other changes improve serviceability and also enhance durability. A new design makes it easier to lubricate the gear teeth on the outside of the main bearing between the upper deck and the sub-frame. "The area is easier to maintain and lubrication of the gear teeth is improved so they will last longer," Vaughn said.

The loaders feature upgraded electronics and diagnostics. "Operators have significant control of the speed of the attachments, and they also have diagnostics beyond what I've seen in any other knuckleboom," Vaughn said. If there is an issue with the machine, a specific diagnosis will pop up on the monitor in the cab — not just a warning light.

The condenser is larger, so the air conditioning is more reliable and the cab cools more quickly. "A loader operator has to open the cab door frequently in the course of a work shift. We improved the AC so that the cab will cool down quickly after each time he has to open the door," Vaughn said. "Operators will also notice how quiet the cab is. The noise level both from inside and outside the cab is greatly reduced."

Caterpillar Forest Products is a leading manufacturer and worldwide marketer of timber harvesting, millyard, road-building and land management equipment. Products are marketed under the Cat®, Prentice™ and CTR brand names through a global independent dealer network.

Caterpillar Forest Products is a division of Caterpillar Inc., the world's leading manufacturer of construction and mining equipment, diesel and natural gas engines, industrial gas turbines and diesel-electric locomotives. The company also is a leading services provider through Caterpillar Financial Services, Caterpillar Remanufacturing Services, Caterpillar Logistics Services and Progress Rail Services. More information is available at www.caterpillar.com.